The present invention relates generally to medical graft materials and, in particular, to medical graft materials derived from tissue materials.
A variety of processed extracellular matrix (ECM) materials have been proposed for use in medical grafting, cell culture, and other related applications. For instance, medical grafts and cell culture materials containing submucosa derived from small intestine, stomach or urinary bladder tissues, have been proposed. See, e.g., U.S. Pat. Nos. 4,902,508, 4,956,178, 5,281,422, 5,554,389, 6,099,567 and 6,206,931. In addition, Cook Biotech Incorporated, West Lafayette, Ind., currently manufactures a variety of medical products based upon small intestinal submucosa under the trademarks SURGISIS®, STRATASIS® and OASIS®.
Medical materials derived from liver basement membrane have also been proposed, for example in U.S. Pat. No. 6,379,710. As well, ECM materials derived from amnion (see e.g. U.S. Pat. Nos. 4,361,552 and 6,576,618) and from renal capsule membrane (see International PCT Patent Application No. WO 03/002165 published Jan. 9, 2003) have been proposed for medical and/or cell culture applications.
Attempts have been made to provide a processed ECM material that retains medically significant substances other than collagen. However, in order to prepare a processed ECM in which undesired components have been removed, the material is typically subjected to a battery of manipulations, which can have undesirable consequences to the desirable components contained within the material. For example, submucosa and other ECM materials have been shown to include a variety of desirable components other than collagen that can contribute to the bioactivity of the materials and to their value in medical grafting and other uses. As examples, ECM materials can include growth factors, cell adhesion proteins, and proteoglycans that can be beneficial when retained in the processed ECM. However, it is difficult to selectively retain these components while removing high levels of undesired components in preparing a medically acceptable graft.
Needs remain for biomaterials that not only possess the necessary physical properties and high levels of biocompatibility and sterility, but also the desired levels of beneficial components. Methods for preparing and using these materials, as well as medical devices formed from these materials are also needed. The present invention addresses these needs.